Integrally formed swivel hook

ABSTRACT

A swivel hook includes a ring portion defining a hollow inner space and having an external engaging section; a first connecting portion having an upper section rotatably received in the inner space of the ring portion; and a second connecting portion rotatably engaged with the engaging section on the ring portion. The swivel hook is integrally formed by positioning the ring portion in a mold, and then injecting plastic material into the mold to sequentially or simultaneously form the first and the second connecting portion, so that the upper section of the first connecting portion is firmly attached to an inner wall surface of the ring portion, and the second connecting portion is engaged with the engaging section on the ring portion; and then downward pulling the first connecting portion of the initially molded swivel hook to allow it to freely rotate in the inner space of the ring portion.

FIELD OF THE INVENTION

The present invention relates to a swivel hook, and more particularly toa swivel hook that is integrally injection molded in one mold tosimultaneously form two swivel connecting portions thereof and cantherefore be produced with simplified procedures and shortened time, aswell as at lowered mold and assembling costs.

BACKGROUND OF THE INVENTION

There are many different types of connecting and fastening devices thatprovide convenient and smooth connecting and fastening functions and aretherefore widely welcome by consumers. Since these conventionalconnecting and fastening devices typically have small volume and areeasy to use, they are often used on backpacks, knapsacks, fasteningbelts, key rings, etc. Similar products are successively developed andintroduced into markets

FIG. 1 is an exploded perspective view of a conventional swivel hook forconnecting and holding two or more different articles together. Theconventional swivel hook includes a main body A and a ring-shaped hangerB. The main body A includes an upper truncated-cone pivotal bearing A1,a hook portion A2 downward extended from the pivotal bearing A1, and alocking element A3 provided at one side of the main body A forreleasably engaging with the hook section A2 to define a holding spacebetween them. The ring-shaped hanger B is provided at a bottom with ahollow connecting bore B1 for engaging with the pivotal bearing A1.There are a plurality of guide slots B2 provided on an inner surface ofthe connecting bore B1.

The truncated-cone pivotal bearing A1 has a bottom diametrically largerthan a top thereof, allowing the pivotal bearing A1 to be upwardextended into the connecting bore B1 from the tapered top. Theconnecting bore B1 is diametrically slightly smaller than the bottom ofthe pivotal bearing A1.

Please refer to FIGS. 2 and 3. The conventional swivel hook shown inFIG. 1 requires two separate molds to injection mold the main body A andthe ring-shaped hanger B. The separately molded main body A andring-shaped hanger B are then assembled together by forcing the pivotalbearing A1 of the main body A into the connecting bore B1 at a specificangle, so that the pivotal bearing A1 is extended through the connectionhole B1 to abut the larger bottom of the pivotal bearing A1 against anupper end of the connecting bore B1 to hold the pivotal bearing A1 tothe ring-shaped hanger B without the risk of separating from theconnecting bore B1.

Since two separate molds are required to injection mold the main body Aand the ring-shaped hanger B, some disadvantages are existed in themanufacturing of the conventional swivel hook. For instance, increasedtime is needed to cut the molds, injection mold the main body A and thehanger B, cool and set he injected plastic material, and assemble themolded main body A and hanger B.

Moreover, the pivotal bearing A1 and the connecting bore B1 are oftenindirectly affected by the conventional manufacturing process and/ordefective material to have relatively weak structural strength, and tendto break or become damaged in the process of forcing the pivotal bearingA1 into the connecting bore B1 to assemble the main body A to the hangerB, resulting in difficulty in controlling the stable quality of thefinished products.

Further, the pivotal bearing A1 and the hanger B are manually assembledto not only complicate the production but also largely increase the timeand labor costs of the swivel hook.

SUMMARY OF THE INVENTION

A primary object of the present invention is to provide an integrallyformed swivel hook that can be produced with simplified procedures andshortened time to upgrade the production efficiency thereof.

Another object of the present invention is to provide an integrallyformed swivel hook that can be produced at reduced mold andmanufacturing costs.

A further object of the present invention is to provide an integrallyformed swivel hook that enables reduced assembling cost.

To achieve the above and other objects, the swivel hook the presentinvention includes a ring portion defining a hollow inner space andbeing provided on an outer circumferential wall surface with an engagingsection; a first connecting portion being injection molded to have aT-shaped upper section engaged with the inner space of the ring portion;and a second connecting portion being injection molded to have two lowerinner ends engaged with the engaging section on the ring portion.

In a preferred embodiment of the present invention, the engaging sectionon the ring portion is a radially outward protruded annular flange or aradially inward annular recess for engaging with the second connectingportion; and the ring portion is made of a metal material, such ascopper, iron, aluminum, etc.

The inner space of the ring portion is in the form of a truncated conehaving a lower end diametrically slightly larger than an upper end, anddefining a downward and outward inclined inner wall surface for the ringportion.

In a most preferred embodiment, the first connecting portion is in theform of a hook-shaped hanger made of a plastic material for an articleto connect and lock thereto; and the second connecting portion is in theform of a ring-shaped hanger made of a plastic material.

The swivel hook is integrally formed by positioning the ring portion ina mold, and then injecting plastic material into the mold tosequentially or simultaneously form the first and the second connectingportion, so that the upper section of the first connecting portion isfirmly attached to the inclined inner wall surface of the ring portion,and the second connecting portion is engaged with the annular engagingsection on the ring portion; and then downward pulling the firstconnecting portion of the initially molded swivel hook to detach it fromthe inclined inner wall surface of the ring portion and allow it tofreely rotate in the inner space of the ring portion.

BRIEF DESCRIPTION OF THE DRAWINGS

The structure and the technical means adopted by the present inventionto achieve the above and other objects can be best understood byreferring to the following detailed description of the preferredembodiments and the accompanying drawings, wherein

FIG. 1 is an exploded perspective view of a conventional swivel hook;

FIGS. 2 and 3 schematically show the manner of assembling a main bodyand a hanger of the conventional swivel hook of FIG. 1;

FIG. 4 is an assembled perspective view of an integrally formed swivelhook according to a preferred embodiment of the present invention with asecond connecting portion thereof shown in phantom line;

FIG. 5 shows perspective and vertical sectional views of two embodimentsof a ring portion of the swivel hook of the present invention;

FIG. 6 shows the step of forming a first connecting portion of theswivel hook of the present invention in a mold;

FIG. 7 shows the step of forming the second connecting portion of theswivel hook of the present invention in the same one mold;

FIG. 8 is a perspective view of a finished product of the integrallyformed swivel hook of the present invention;

FIG. 9 shows one manner of making the first and the second connectingportion of the swivel hook of the present is invention to rotateindependently relative to the ring portion; and

FIG. 10 includes two enlarged views of the circled areas in FIGS. 7 and9, respectively.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Please refer to FIGS. 4 and 5, in which an integrally formed swivel hookaccording to a preferred embodiment of the present invention is shown.As shown, the integrally formed swivel hook includes a ring portion 1defining a hollow inner space 11, and being provided on an outercircumferential wall surface with an engaging section 12; a firstconnecting portion 2 being injection molded to have a T-shaped uppersection engaged with the inner space 11 of the ring portion 1; and asecond connecting portion 3 being injection molded to have two lowerinner ends engaged with the engaging section 12 on the ring portion 1

In the preferred embodiment, the engaging section 12 on the outer wallsurface of ring portion 1 may be either a radially protruded annularflange, as shown in the upper part of FIG. 5, or a radially inwardannular recess, as shown in the lower part of FIG. 5, for engaging withthe second connecting portion 3; and the ring portion 1 may be made of ametal material, such as copper, iron, aluminum, etc.

The inner space 11 of the ring portion 1 is in the form of a truncatedcone to have a lower end diametrically slightly larger than an upper endand thereby defines a downward and outward inclined inner wall surface13 for the ring portion 1.

As can bc seen from FIG. 4, the first connecting portion 2 is in theform of a hook, to which an article could be connected and locked, andis made of a plastic material through injection molding; and the secondconnecting portion 3 is in the form of a ring-shaped hanger, and is alsomade of a plastic material through injection molding.

Please refer to FIG. 6. To integrally form the swivel hook of thepresent invention, first position the ring portion 1 in a mold 4 used toform the swivel hook. Then, inject the plastic material for forming oneof the first and the second connecting portion 2, 3 into the mold 4. Inthe illustrated embodiment of the present invention, the firstconnecting portion 2 is injection molded prior to the forming of thesecond connecting portion 3. To form the first connecting portion 2,first inject the plastic material into the inner space 11 of the ringportion 1 to form the substantially T-shaped upper section. The injectedplastic material is expanded due to high temperature to adhere to theinclined wall surface 13 at the inner space 11 of the ring portion 1. Alower section below the T-shaped upper section of the first connectingportion 2 is in the form of a hook-shaped hanger. When the injectedplastic material is cooled and set, the first connecting portion 2 ismolded. Since the cooled plastic material is subject to shrinkage, themolded first connecting portion 2 would naturally tightly contact withthe inclined wall surface 13 of the inner space 11.

FIG. 7 shows the forming of the second connecting portion 3 of theswivel hook of the present invention. First, inject the plastic materialinto a cavity of the mold 4 for molding the second connecting portion 3.The injected plastic material is expanded due to high temperature,causing the plastic material at the two inner ends of the secondconnecting portion 3 to firmly adhere to the engaging section 12 on theouter wall surface of the ring portion 1. When the plastic material iscooled, the molded second connecting portion 3 is naturally tightlyengaged with the engaging section 12 of the ring portion 1. FIG. 8 showsa finished product of the integrally formed swivel hook of the presentinvention molded in the manner as described above with reference toFIGS. 6 and 7.

There is not particular restriction to the sequence of theabove-mentioned injection molding procedures. It is also acceptable tofirst injection mold the second connecting portion 3, or to injectionmold the first and the second connecting portion 2, 3 at the same time.

When the first and the second connecting portion 2, 3 are initiallymolded, the first connecting portion 2 is firmly attached to theinclined inner wall surface 13 of the ring portion 1. At this point, anoperator may hold the first and the second connecting portion 2, 3 withtwo hands to apply two opposite forces, as indicated by the two arrowsin FIG. 9. Alternatively, the operator may hold the second connectingportion 3 in place with one hand, and pulls the first connecting portion2 downward with another hand. In any one of these manners, the T-shapedupper section of the first connecting portion 2 under the pull isshifted downward in the truncated-cone-shaped inner space 11 toward thediametrically larger lower end, such that the first connecting portion 2is no longer firmly attached to but is in rotatable contact with theinclined inner wall surface 13 of the ring portion 1. The T-shaped uppersection of the first connecting portion 2 is now abutted at a lowerhorizontal surface on an upper end of the ring portion without the riskof downward moving out of the ring portion 1, and may be freely rotatedin the inner space 11 of the ring portion 1 independent of the secondconnecting portion 3. FIG. 10 shows at an upper and a lower positionthereof enlarged views of the circled areas in FIGS. 7 and 9,respectively, to describe the manner of detaching the T-shaped uppersection of the first connecting portion 2 from the inclined inner wallsurface 13 of the ring portion 1.

In the present invention, the swivel hook is integrally formed bypositioning the ring portion 1 in the mold 4, and then subsequently orsimultaneously injection molding 1, 1 the first and the secondconnecting portion 2, 3 using the same mold 4, so that the twoconnecting portions 2, 3 are respectively engaged with the inner and theouter wall surface of the ring portion 1 at the same time, and thendownward pulling the first connecting-portion 2 of the initially moldedswivel hook to allow it to rotate freely in the ring portion 1. It isnot necessary to cut two molds, and the swivel hook could be completedthrough simplified and time-shortened manufacturing procedures tolargely upgrade the production efficiency and reduce the mold andassembling costs.

The present invention has been described with a preferred embodimentthereof and it is understood that many changes and modifications in thedescribed embodiment can be carried out without departing from the scopeand the spirit of the invention that is intended to be limited only bythe appended claims.

1. An integrally formed swivel hook, comprising: a ring portion defininga hollow inner space and being provided on an outer circumferential wallsurface with an engaging section; a first connecting portion beinginjection molded to engage an upper section with said inner space ofsaid ring portion; and a second connecting portion being injectionmolded to engage with said engaging section on the outer circumferentialwall surface of said ring portion.
 2. The integrally formed swivel hookas claimed in claim 1, wherein said engaging section is selected fromthe group consisting of a radially protruded annular flange and aradially inward annular recess.
 3. The integrally formed swivel hook asclaimed in claim 1, wherein said ring portion is made of a metalmaterial.
 4. The integrally formed swivel hook as claimed in claim 1,wherein said inner space of said ring portion is in the form of atruncated cone having a lower end diametrically larger than an upper endof said inner space.
 5. The integrally formed swivel hook as claimed inclaim 1, wherein said inner space of said ring portion defines adownward and outward inclined inner wall surface for sail ring portion.6. The integrally formed swivel hook as claimed in claim 1, wherein saidfirst connecting portion is in the form of a hook-shaped hanger, towhich an article is connected and locked.
 7. The integrally formedswivel hook as claimed in claim 1, wherein said first connecting portionis made of a plastic material.
 8. The integrally formed swivel hook asclaimed in claim 1, wherein said second connecting portion is in theform of a ring-shaped hanger, to which an article is connected.
 9. Theintegrally formed swivel hook as claimed in claim 1, wherein said secondconnecting portion is made of a plastic material.